Cities are often blamed for being the main emitters of greenhouse gases (up to 75% of CO2emissions are attributed to cities due to the energy consumption tied to the activities they host: transport, industry, etc. But they are also the first to suffer from climate change: extreme climate events have more drastic outcomes in highly populated areas and the harmful effects of polluting activities are felt more strongly.
Aware of the role that they can play, cities have been organising themselves into networks since the 1990s (C40, Cities Climate Leadership Group, ICLEI Local Governments for Sustainability, etc.) to share their experiences and reinforce their actions. Their commitment now singles them out as leading players: for example, London has announced an 80% reduction in its emissions by 2050, which is one of the most ambitious objectives targeted at local authority level or even national level.